In preparation for today's "Back to the Mac" event Apple has taken its online Apple Stores offline. 

Both the US and UK stores are now showing the familiar "We'll be back soon" Post-It note. 

We expect to see a preview of Mac OS X Lion, but the store is likely to reopen with new versions of iLife, iWork, and potentially a new smaller and lighter MacBook Air

Be sure to tune in for our live feed of Apple's "Back to the Mac" event at 6pm.